dry sump questions

[gt350hr]

   I am positive you Nascar friend is still using DLC coated wrist pins which can survive in a lesser oil environment. He wouldn't even consider a non coated pin , and not only for the fact his rods do not have bushings. Oh yes you failed to mention his pin diameters are under .800. Another need for a stiffer wrist pin. Wrist pin issues began first in the Truck and Busch series engines when they were still using .927 diameter pins. Much of it was due to camshaft timing with the 9.5 compression rule and then legal 18* heads. The exhaust pin bores were melting ( not the intake ) and causing piston failure. DLC coated pins solved that and were soon being used by cup engine builders too. Crank case vacuum came after that  along with minimum weight rules.

[mbrunson427]

For an FE application what would those in the know recommend for a oil tank size?. Can someone also explain the differences/advantages of 3/4/5 stages dry sump pumps?. I am only assuming it is nothing more than the amount of plumbed pickups in the oil pan?. Any other recommendations are appreciated...John

I still don't think Fordman's original question has been answered yet. I've learned a lot by everybody going back and forth on this, but the original intent of the thread still hasn't gotten much attention. I guess it would probably help to know the application.....

[scott foxwell]

So that gives the pins was flexing more with "higher vaccum"
make sense in a way that there was bigger difference in pressure
over/under piston....

That's possible theoretically but we're only talking a few psi difference.

[scott foxwell]

Where does the wrist pin get most of it's oiling from?

I like discussions like this because they get me thinking beyond what I think I already know...
It's not personal.

  Lower performance , production engines usually rely on splash oiling. Oil being "thrown around" in the crank case. For splash oiling to work , there has to be oil droplets of "fog" as you put it , present or and oil squirt hole drilled into the connecting rod ( older small block Fords for example).
  Performance and race engines usually have "forced pin oiling" that comes from oil drains located in the oil ring groove which put oil directly on top of the wrist pin. Often there are two holes per side. Sometimes broaches are added to the sides of the pin bore as an additional source. Very high end race engines ( and high turbo boosted engines) have "oil squirters" off of the mains aimed at the underside of the pistons to cool them and that "splash oiling" also oils the wrist pins. Scrapers and windage screens are after the fact when it comes to rod throws.

I was leaning more toward what is the source of oil, not how it might be directed to the pin. I see it as two places; the rod throws and oil flying off the spinning crank.

[scott foxwell]

   I am positive you Nascar friend is still using DLC coated wrist pins which can survive in a lesser oil environment. He wouldn't even consider a non coated pin , and not only for the fact his rods do not have bushings. Oh yes you failed to mention his pin diameters are under .800. Another need for a stiffer wrist pin. Wrist pin issues began first in the Truck and Busch series engines when they were still using .927 diameter pins. Much of it was due to camshaft timing with the 9.5 compression rule and then legal 18* heads. The exhaust pin bores were melting ( not the intake ) and causing piston failure. DLC coated pins solved that and were soon being used by cup engine builders too. Crank case vacuum came after that  along with minimum weight rules.

I didn't fail to mention anything. I just passed along what he said.

"Nothing eliminated the problem until we went to stiffer pins."

The guy who wrote that is responsible for Cup, Truck, Bush, Infinity, and any other venue that HMS supplies engines for and has been there a LONG time.

[blykins]

For an FE application what would those in the know recommend for a oil tank size?. Can someone also explain the differences/advantages of 3/4/5 stages dry sump pumps?. I am only assuming it is nothing more than the amount of plumbed pickups in the oil pan?. Any other recommendations are appreciated...John

I still don't think Fordman's original question has been answered yet. I've learned a lot by everybody going back and forth on this, but the original intent of the thread still hasn't gotten much attention. I guess it would probably help to know the application.....

Yes sir, it would.  The size of the tank depends on the application. 

[TomP]

I am just more curious what John is building that warrants a dry sump?

Perhaps he dug up Bob MacLean's crashed GT40 and is restoring it? Or maybe like one guy I knew, put a Mustang II suspension without spacing it lower and using drop spindles and is using a  dry sump to solve the oil pump hitting the rack issue?

Tank size depends on available space too.

[gt350hr]

   The guy that wrote this is responsible for conical and spherical dish piston tops that EVERYBODY in Nascar copied. I still don't walk on water and never will. You probably remember me from PRI.

[Barry_R]

Cool to see how small this circle really is.  Randy Gillis was at JE and made those early spherical dish pistons.  He talked me into using those in one of my early EMC entries.  They work well.

[66FAIRLANE]

Great discussion. Its always an interesting argument when everyone seems to have valid points!

[scott foxwell]

   The guy that wrote this is responsible for conical and spherical dish piston tops that EVERYBODY in Nascar copied. I still don't walk on water and never will. You probably remember me from PRI.

If this is directed at me, I'm not sure what that has to do with anything, and I don't remember anyone named gt350hr from PRI.

[cammerfe]

There was a time, some years ago, when I occupied part of most days at Jack Roush's 'Prototype Engine Shop'. With his permission, I was doing a multi-month series on building an engine---writing for Mustang Illustrated Magazine. The PES was the place, at the time, where all the NASCAR engines were built.

Depending on what I was observing and photographing, I pretty-much had the run of the place. But there were a few areas where they kept the doors closed. Talking to Jack one day, he pointed to one of those unmarked doors and said, "We're doing ongoing exploration regarding oil pans in there. There's a lot of power to be found in the sump of an engine."

This discussion points-out several aspects of the truth of that statement. It's still true today, even with all we've learned in the interim.

KS

[Fordman]

Tom.....My application is drag racing. Kids are moved out, sold a property so I finally have a budget for some fun. I actually learned a lot with this thread. My opinion now is that return VS expense and hassle I wont be going dry sump. I think for what I'm doing and good wet sump pan design with kickout and crank scraper, windage tray that will be fine.....John

[andyf]

Tom.....My application is drag racing. Kids are moved out, sold a property so I finally have a budget for some fun. I actually learned a lot with this thread. My opinion now is that return VS expense and hassle I wont be going dry sump. I think for what I'm doing and good wet sump pan design with kickout and crank scraper, windage tray that will be fine.....John

Take a look at the cars going as fast as you want to go and see if they are dry sump or not. My guess is that they are not. Drag racers have figured out how to run 8 and 9 second cars with wet sump pans. Pro Stock uses dry sump as do some Comp guys but most drag racers have figured out how to make a wet sump work. There are some really nice advantages that come with a dry sump setup but it is a hassle in a door car and it is expensive.

[cjshaker]

An accumulator will help you out tremendously. Get the big one for some extra reserve.